WO2014030242A1

WO2014030242A1 - Combustion system

Info

Publication number: WO2014030242A1
Application number: PCT/JP2012/071327
Authority: WO
Inventors: 敬二郎塩出; 正田口
Original assignee: やまと総合環境株式会社
Priority date: 2012-08-23
Filing date: 2012-08-23
Publication date: 2014-02-27
Also published as: EP2889538A1; TW201408953A; JPWO2014030242A1

Abstract

A combustion system provided with: a fuel tank; a pump for adding pressure to fuel supplied from the fuel tank; a first nozzle part for spraying the pressurized fuel in the combustion chamber; a supply pipe for coupling the first nozzle part and the pump, and through which the pressurized fuel flows; a connection part provided along the supply pipe near the first nozzle part; a supply unit for supplying water to the supply pipe via the connection part; and a second nozzle part interposed between the supply unit and the connection part for atomizing water and spraying in the connection part.

Description

Combustion system

The present invention relates to a combustion system that can generate water emulsion fuel and burn it.

In the conventional water emulsion fuel supply device (first water emulsion fuel supply device), the fuel pressurized by the eruption pump is maintained at a constant pressure by the relief valve, and the combustion amount is determined by the oil amount adjustment valve, Further, when passing through the mixer, water is injected by a proportional water injection mechanism. Here, water and fuel are mixed and supplied to the burner.

In this conventional water-emulsion fuel supply device, the internal pressure of the mixer changes because the passage resistance of the burner (9) fluctuates due to the increase or decrease in the combustion amount or the water addition rate. In addition, since the internal pressure of the mixer also changes due to fluctuations in the amount of combustion, even in the proportional water injection mechanism, the pressure at the injection point changes significantly, causing a change in the injection amount and causing a fire or the like.

Therefore, in the improved conventional water emulsion fuel supply device (second water emulsion fuel supply device), an emulsion pump is provided at the outlet of the mixer, and a pressure reducing valve is provided between the mixer outlet and the mixer inlet. It was installed in a direction to keep the pressure of. As a result, even if the combustion amount and the water content change, the pressure before and after the oil amount adjusting valve and the proportional water injection mechanism is kept constant so that smoke and fire do not occur (see, for example, Patent Document 1).

JP-A-5-157221

However, in the configuration of the first water emulsion fuel supply device, the pressure is controlled by the pressure between the jet pump and the discharge amount of the burner nozzle, and the pressure in the pipe is reduced due to the correlation that the fuel amount decreases as the water amount increases. Does not fluctuate significantly. Therefore, it is unlikely that the phenomenon described in Patent Document 1 will occur.

In the second water emulsion fuel supply device, a dedicated emulsion pump and a pressure reducing valve are required. When the fuel mixed with water is sent to the pressure reducing valve side, friction expansion occurs in the pressure reducing valve, resulting in lack of lubricity, and pressure adjustment may become impossible (failure). Further, the second water emulsion fuel supply device basically assumes a large-capacity combustion device (ship, large electric furnace) and cannot be applied to a general combustion device at all.

Furthermore, when a dedicated emulsion pump is provided, it is necessary to match the drive of the emulsion pump with the signal from the combustion device side, and the manufacturer's consent is hardly obtained, which is not realistic.

The present invention is a combustion system capable of coping with all liquid fuels in a unified manner, enabling mixed combustion of petroleum fuel (or a mixed fuel of petroleum fuel and other liquid fuel) and water, and is difficult to burn. The purpose is to provide a combustion system that can prevent global warming and reduce harmful exhaust gas by clean combustion of fuel.

The combustion system includes a fuel tank, a pump that pressurizes the fuel supplied from the fuel tank, a first nozzle portion that injects the pressurized fuel into the combustion chamber, the first nozzle portion, and the pump. A supply pipe through which the pressurized fuel passes and connects, a connection part provided in the middle of the supply pipe in the vicinity of the first nozzle part, and water is supplied into the supply pipe through the connection part A supply unit; and a second nozzle part interposed between the supply unit and the connection part and capable of atomizing and injecting water into the connection part.

According to the present invention, since water and main liquid fuel are not mixed in advance and only water is injected into the main liquid fuel, the influence of nozzle clogging due to sludge and fine particles in the fuel can be avoided. And the long-term stable operation of a combustion system is securable from the ease of the apparatus which can manage only water independently. In addition, since the water content can be adjusted only with water according to the type and capacity of the combustion device, the device structure can be simplified, and the size and cost can be reduced. Furthermore, the problem of non-ignition and the failure of the fuel injection pump found in the conventional apparatus can be solved. In addition, liquid fuels with different fuel components have been required to be handled as individual water emulsion devices, but according to the present invention, a unified combustion system can be used regardless of the type or standard of the combustion furnace or internal combustion engine. In addition, the versatility can be enhanced and a wider range of environmental measures can be taken.

The system diagram which showed typically the whole structure of the combustion system of 1st Embodiment. Sectional drawing which expanded and showed the chamber of the combustion system shown in FIG. The microscope picture of the fuel sample extract | collected from the inspection hole of the chamber shown in FIG. The display screen on the computer which showed the measurement result of the particle diameter of each water particle of the microscope picture shown in FIG. The graph which showed the relationship between the pressure difference between fuel (main liquid fuel) and the water injected from a water injection nozzle, and the average particle diameter of a water particle. Sectional drawing which showed the chamber and 2nd nozzle part of the combustion system of 2nd Embodiment. Sectional drawing which showed the chamber and 2nd nozzle part of the combustion system of 3rd Embodiment. The system diagram which showed typically the whole structure of the combustion system of 4th Embodiment. The system diagram which showed typically the whole structure of the combustion system of 5th Embodiment.

1st Embodiment of a combustion system is demonstrated with reference to FIGS.

As shown in FIGS. 1 and 2, a combustion system 11 includes a combustion device 12 (main liquid fuel operation device) constituted by a boiler, a water emulsion fuel device 13 that generates water emulsion fuel, and a water emulsion fuel device. 13 includes a high pressure pump device 14 (supply unit) that supplies water to 13, a combustion device 12, a water emulsion fuel device 13, and a control device 15 that controls the high pressure pump device 14.

The combustion system 11 includes a fuel tank 16 in which fuel (main liquid fuel, for example, petroleum fuel) is stored, a fuel injection pump 17 (pump) connected to the fuel tank 16 and receiving fuel supply from the fuel tank 16, a fuel A fuel pipe 18 that connects the tank 16 and the fuel injection pump 17, a first flow meter 21 provided in the fuel pipe 18, and a combustion nozzle 22 that injects fuel pressurized by the fuel injection pump 17 into the combustion chamber (the first 1 nozzle part), a combustion device 12 provided with a combustion chamber, a supply pipe 23 connecting the combustion nozzle 22 and the fuel injection pump 17, a first pressure gauge 24 provided in the middle of the supply pipe 23, and a combustion nozzle A first electromagnetic valve provided in the middle of the supply pipe 23 at a position between the combustion nozzle 22 and the chamber 25 and a chamber 25 (connection portion) provided in the supply pipe 23 in the vicinity of 22. 6, a circulation line 27 connecting the supply pipe 23 and the fuel pipe 18, a second electromagnetic valve 28 provided in the first branch 27 </ b> A of the circulation line 27, and a flow rate adjustment provided in the second branch 27 </ b> B of the circulation line 27. A pressure electromagnetic valve 31, a high-pressure pump device 14 (supply unit) for supplying water into the supply pipe 23 via the chamber 25 (connection portion), and a second interposed between the high-pressure pump device 14 and the chamber 25. Nozzle portion 32.

Among these, the fuel injection pump 17 (first pump), the first pressure gauge 24, the chamber 25 (connecting portion), the circulation line 27, the second electromagnetic valve 28, and the flow pressure regulating electromagnetic valve 31 are the water emulsion fuel device. 13 included. The combustion nozzle 22 is included in the combustion device 12. The first solenoid valve 26 turns fuel supply ON / OFF.

The pressure of the fuel pressurized by the fuel injection pump 17 and passing through the supply pipe 23 is, for example, 1.0 MPa. The pressure of the fuel in a general combustion furnace is in the range of 0.3 MPa to 10 MPa. Therefore, also in this embodiment, the pressure of the fuel pressurized by the fuel injection pump 17 can be appropriately set in the range of 0.3 MPa to 10 MPa. The fuel stored in the fuel tank 16 is, for example, heavy oil (for example, A heavy oil, C heavy oil), but other fuels (such as light oil) may be used. The flow rate at which the fuel flows through the supply pipe 23 is, for example, 0.2 m / s, but may be 0.2 m / s or more.

As shown in FIG. 1, the high-pressure pump device 14 (supply unit) includes a water tank 33 that stores water therein, water supplied from the water tank 33, and water that is pressurized by the second nozzle portion 32. A high pressure pump 34 (second pump) to be sent, a water supply line 35 connecting the high pressure pump 34 and the second nozzle portion 32, a return circuit 36 returning from the water supply line 35 into the water tank 33, and a return circuit 36 A flow rate adjusting valve 37 provided in the middle, a second pressure gauge 39 provided in the middle of the water supply line 35, and a second flow meter 38 provided in the middle of the water supply line 35 are provided.

Note that the configuration of the high-pressure pump device 14 (supply unit) is not necessarily integrated. For example, when water purification is necessary, the high-pressure pump device 14 may not include the tank function (water tank 33). In this case, the tank function (water tank 33) is provided separately from the high-pressure pump device 14.

The high-pressure pump device 14 can supply water (main liquid fuel) with water having a pressure higher than that of the pressurized fuel (main liquid fuel). The pressure of water pressurized by the high-pressure pump 34 is, for example, 1.5 MPa, but as appropriate within a range 0.5 MPa to 10 MPa higher than the pressure of fuel pressurized by the fuel injection pump 17 as will be described later. Can be set. A third electromagnetic valve 41 is interposed between the chamber 25 and the high-pressure pump device 14. The high-pressure pump 34 is, for example, a commercially available plunger pump, but may be a commercially available diaphragm pump. Further, a metering pump can be employed as the high-pressure pump 34. In this case, it is possible to supply water at a constant pressure and a constant discharge pressure by directly connecting to the water supply facility without using the water tank 33, so that further compactness can be achieved.

As shown in FIG. 2, the chamber 25 (connection portion) is configured to be detachable from a supply pipe 23 or the like of an existing boiler facility or the like. The chamber 25 is continuous with the first end 42 connected to the upstream side of the supply pipe 23, the second end 43 connected to the downstream side of the supply pipe 23, and the first end 42, and the supply pipe The first portion 44 having an inner diameter larger than the inner diameter of the first portion 44, the second portion 45 that is continuous with the first portion 44 and the second end portion 43 and has a tapered shape, and the second end portion 43. And an inspection hole 46.

The second nozzle portion 32 is connected to the first portion 44 of the chamber 25 in a direction orthogonal to the direction in which the supply pipe 23 extends. In the present embodiment, the second nozzle part 32 is constituted by one. The second nozzle portion 32 is provided at a position as close as possible to the chamber 25. In the present embodiment, for example, a standard straight nozzle (orifice diameter: CP small hole diameter nozzle 0.3 mm) manufactured by Ikeuchi Co., Ltd. was used for the second nozzle portion 32. Other types of nozzles can also be used for the second nozzle portion 32. For example, the small hole diameter may be about 0.1 mm to 3 mm, and the shape of the nozzle may be a full cone type or a hollow cone type. Further, the types of the second nozzle section 32 are various, and the selection varies depending on the type of burner, and there are ON / OFF type control, three-position position type control, or proportional control type, which varies depending on the situation of each combustion device. .

The installation angle of the second nozzle part 32 is not limited to the direction orthogonal to the direction in which the supply pipe 23 extends. As indicated by a broken line in FIG. 2, the direction may be an oblique direction with respect to the direction in which the supply pipe 23 extends, or may be a direction parallel to the direction in which the supply pipe 23 extends. In particular, when the flow velocity of the fuel (main liquid fuel) in the pipe is slow, the second nozzle portion 32 is attached to be inclined with respect to the direction in which the supply pipe 23 extends (the flow direction of the fuel), so It is better to promote dispersion and mixing.

As shown in FIG. 1, in this embodiment, the fuel in the fuel tank 16 is sent to the fuel injection pump 17. The fuel pressurized by the fuel injection pump 17 is supplied to the fuel injection pump 17 through the supply pipe 23. In the chamber 25, pressurized water is jetted from the second nozzle part 32. The water emulsion fuel produced by the high-pressure injection of water is injected from the combustion nozzle 22 into the combustion chamber of the combustion device 12 and burned.

When an abnormality occurs in any of the combustion systems 11 of the present embodiment, the flow regulating solenoid valve 31 of the circulation line 27 is opened and adjusted to the main liquid fuel amount suitable for the air amount at the time of water emulsion fuel. Avoid black smoke. For example, when water injection stops due to a stop of the high-pressure pump 34, a blockage of the second nozzle portion 32, an instantaneous power failure, a pressure abnormality, etc., the main liquid fuel amount increases and smoke generation due to a shortage of air amount is considered (air auto Except when a regulator is installed.) As an emergency measure, the flow regulating solenoid valve 31 is opened, and the main liquid fuel is reduced to an amount commensurate with the amount of air to prevent black smoke from being generated in an abnormal state.

In the case of water emulsion fuel with a high water content, non-ignition is prevented by the following method. That is, during the pre-purge of the fuel injection pump 17 (until the pressure is stabilized), the second electromagnetic valve 28 is opened for several seconds, and the main pipe in the supply pipe 23 to the fuel pipe 18, the fuel injection pump 17, and the chamber 25 is opened. A liquid fuel and a water emulsion fuel having a high water content are mixed. Thereby, non-ignition can be prevented. When non-ignition occurs, the moisture content is 20% or more. When the moisture content is 20% or less, almost no ignition occurs. The operation adjustment of the combustion device 12, the water emulsion fuel device 13, and the high-pressure pump device 14 is performed by a sequencer of the control device 15.

The water atomization in the second nozzle part 32 will be described. In the present invention, water is injected into the fuel flowing through the supply pipe 23 from the second nozzle portion 32 (fine nozzle) at high pressure, and water is finely divided by the discharge speed (or momentum) of the high pressure injection and the reaction force of the main liquid fuel. At the same time, the water particles are mixed so as to be evenly dispersed in the fuel. The phenomenon of the present invention is obtained by replacing the atomization theory in the air with the liquid, and in the air, the average particle diameter at a point of 300 mm is generally used, but in the liquid, it is much faster than in the air. Fine particles at speed.

It should be noted that the combustion of water emulsion fuel is improved over conventional combustion based on the following principle. When water emulsion fuel is sprayed into the combustor, the water particles contained in the fuel oil droplets are heated by the heat in the furnace and reach the boiling point, causing a micro explosion, and the spray oil droplets become secondary fine particles. Make it. In this way, when the fuel is instantly atomized, the contact area with the air is greatly increased and combustion close to complete combustion is achieved, and the generation of unburned carbon (soot) and NOx in the combustion exhaust gas is suppressed. Combustion is possible. Moreover, since the excess air required for combustion can be kept low by increasing the contact area with air, an energy saving effect can be obtained accordingly.

When petroleum fuel is burned in the air, the components in the combustion gas that are mainly produced when it is burned completely are carbon dioxide, water, nitrogen oxides and sulfur oxides. However, complete combustion is actually impossible, and soot and carbon monoxide are emitted in addition to the components described above. These are produced by incomplete combustion, but to suppress these components, better mixing with air. By adding water to the fuel and increasing the mass of the sprayed fuel, the amount of air entrained in the fuel spray bundle can be increased, the local excess air ratio in the combustion region can be increased, and the combustion efficiency can be improved.

By the way, prior to the construction of the combustion system 11, the inventors of the present invention conducted an experiment to investigate the optimum conditions of the fuel pressure and the pressure of water added to the fuel. The experiment was conducted by examining the relationship between the pressure difference between the pressure of the fuel (main liquid fuel) and the pressure of water and the average particle size (or maximum particle size) of water particles. A sample of water emulsion fuel in each condition was taken from the inspection hole 46 of the chamber 25.

The inventors examined the dispersion state of water particles under a microscope (for example, VH5500 manufactured by Keyence) and measured the average particle size (or maximum particle size) of the water particles for each sample. For example, FIG. 3 shows a photomicrograph taken at a magnification of 2000, and the particle size (average particle size) of water particles is measured in such a photomicrograph (image). The portion where the round water particles are not visible is water particles and fuel of 450 nm or less. The particle diameters of the water particles 1 to 5 in FIG. 1-No. This corresponds to a measurement result of 5.

FIG. 5 is a graph showing the relationship between the pressure difference between the fuel (main liquid fuel) pressure and the water pressure and the average particle size of the water particles. In FIG. 5, the portion of 1 MPa in the horizontal axis indicates that the pressure of water injected into the fuel (main liquid fuel) by the second nozzle portion 32 is 1 MPa higher than the pressure of the fuel.

In addition, as a form of water particles in the emulsion fuel, it is desirable that the water particles have a particle diameter that is smaller than the fuel injection droplet diameter and is mixed with a uniform water content. Therefore, when the average particle diameter of the fuel injection droplets is 30 μm to 50 μm, at least the average diameter of the water particles is theoretically 10 μm or less. Generally, it can be used as a water emulsion fuel when the average particle diameter of water particles is 14 μm or less, and the case where the average particle diameter of water particles is 10 μm or less is ideal as a water emulsion fuel.

According to the experimental results of FIG. 5, it was confirmed that when the water pressure was increased with respect to the main fuel pressure, the particle size of the water particles gradually decreased. For this reason, it is preferable that the water added with respect to the pressurized fuel has a pressure higher than the pressure of the fuel pressurized by the fuel injection pump 17, for example, a pressure higher by about 0.5 MPa to 10 MPa.

According to this embodiment, the combustion system 11 includes a fuel tank 16, a pump that pressurizes the fuel supplied from the fuel tank 16, a first nozzle unit that injects the pressurized fuel into the combustion chamber, A supply pipe 23 that connects the one nozzle part and the pump and through which pressurized fuel passes, a connection part provided in the middle of the supply pipe 23 in the vicinity of the first nozzle part, and a supply pipe 23 via the connection part A supply unit for supplying water therein, and a second nozzle part 32 which is interposed between the supply unit and the connection part and can atomize and inject water into the connection part.

According to this configuration, high-pressure water is mixed with the pressurized fuel to produce a water-emulsion fuel, and thereafter, the water-emulsion fuel can be maintained in a high-pressure state until it is used in the first nozzle part. Thereby, in the microparticulated water particles, the internal pressure due to the surface tension is increased, particle collapse and particle bonding are prevented, and aggregation of water in the water emulsion fuel can be prevented. Further, when heavy oil is used as fuel, heating is required in each part of the supply pipe 23 in order to reduce the viscosity. According to this embodiment, the water emulsion fuel is supplied in a pressurized state. Due to the presence in the tube 23, water particles are not vaporized in the water emulsion fuel even when heated.

Further, according to this embodiment, since the water emulsion fuel can be generated immediately before being used in the first nozzle portion, there is no time for water to aggregate in the water emulsion fuel as described above. For this reason, it can prevent that the said malfunction arises in water emulsion fuel. Furthermore, according to the present embodiment, the mixer and the water emulsion fuel dedicated pump that are conventionally required are not required, and the apparatus configuration can be simplified, reduced in cost, and made compact. In addition, the existing equipment does not require major modifications. Further, since the water emulsion fuel can be generated without using an expensive surfactant, the running cost of the apparatus can be reduced.

Also, the water pressure is 0.5 MPa to 10 MPa higher than the pressure of the pressurized fuel. According to this configuration, water fine particles are sufficiently formed in the water emulsion fuel by the momentum of the water injection force. As a result, water particles in the fuel in the combustion chamber receive the heat in the combustion chamber and reach the boiling point to cause a micro explosion, whereby the sprayed oil droplets can be made into secondary particles. For this reason, the area where the fuel comes into contact with the air is greatly increased, combustion close to complete combustion is achieved, and clean combustion with reduced generation of unburned carbon (soot) and NOx in the combustion exhaust gas can be achieved.

Note that the provision of the connection portion in the vicinity of the first nozzle portion means that the connection portion is in the vicinity of the first nozzle portion, and the end portion on the first nozzle portion (combustion nozzle 22) side in the supply pipe 23. Thus, it indicates that the connecting portion is provided within a range of approximately one third of the total length of the supply pipe 23 (more preferably, 10% to 20% with respect to the total length of the supply pipe 23). .

The connecting portion is a chamber 25 that can be attached to and detached from the supply pipe 23. According to this configuration, the fuel can be changed to the water emulsion fuel without significantly changing the existing equipment, and the initial cost at the time of introduction can be reduced.

The second nozzle part 32 is inclined with respect to the direction in which the supply pipe 23 extends. As a result, water can be injected at a constant angle with respect to the fuel flow direction, turbulent flow can be generated in the connecting portion, and mixing of the main liquid fuel and water particles can be promoted, resulting in high quality. Water emulsion fuel can be produced.

In the first embodiment, the throttle unit 51 of the second embodiment may be provided on the downstream side of the second nozzle unit 32 in the chamber 25 (connection unit).

A second embodiment of the combustion system will be described with reference to FIG. In the combustion system 11 of the second embodiment, the chamber 25 and the second nozzle portion 32 are different from those of the first embodiment, but other parts are common to the first embodiment. For this reason, a different part from 1st Embodiment is mainly demonstrated, and illustration is abbreviate | omitted or abbreviate | omitted about the part which is common in 1st Embodiment. The combustion system 11 of the second embodiment has the same configuration as the overall configuration of the first embodiment shown in FIG.

The chamber 25 (connection portion) is configured to be detachable with respect to the supply pipe 23 of the existing boiler equipment or the like. The chamber 25 is continuous with the first end 42 connected to the upstream side of the supply pipe 23, the second end 43 connected to the downstream side of the supply pipe 23, and the first end 42, and the supply pipe The first portion 44 having an inner diameter larger than the inner diameter of the first portion 44, the throttle portion 51 provided in the first portion 44 and having a smaller inner diameter than the other portions of the first portion 44, the first portion 44, and the second portion. A second portion 45 that is continuous with the end portion 43 and has a tapered shape, and an inspection hole 46 provided in the second end portion 43 are included.

The second nozzle part 32 has a plurality of (for example, three) second nozzles 32A. The number of second nozzles 32A may be two, or four or more. The second nozzles 32 </ b> A are provided in the first portion 44, and are alternately provided along the direction in which the supply pipe 23 extends (the fuel flow direction). Each second nozzle 32 </ b> A is installed obliquely with respect to the direction in which the supply pipe 23 extends. As an example, the second nozzle 32A is a standard straight nozzle made by Ikeuchi Co., Ltd. (orifice diameter: CP small hole diameter nozzle 0.3 mm), but other types of nozzles can also be used as in the first embodiment. is there. In addition, the fuel pressure and water pressure conditions are the same as in the first embodiment. The throttle part 51 is provided on the downstream side of the second nozzle part 32.

According to the present embodiment, the second nozzle portion 32 includes a plurality of second nozzles 32A, and the plurality of second nozzles 32A are arranged alternately along the direction in which the supply pipe 23 extends. According to this configuration, it becomes easier to cause turbulent flow in the connecting portion, and the mixing of the main liquid fuel and water particles can be further promoted.

The connection portion is provided on the downstream side of the first portion 44 provided with the second nozzle portion 32 and the second nozzle portion 32 of the first portion 44, and has an inner diameter that is smaller than that of other portions in the first portion 44. And a narrowed throttle part 51.

According to this configuration, Karman vortices can be generated on the downstream side of the throttle portion 51, whereby the main liquid fuel and water particles can be mixed and the water particles can be dispersed in the main liquid fuel.

A third embodiment of the combustion system 11 will be described with reference to FIG. In the combustion system 11 of the third embodiment, the chamber 25 and the second nozzle part 32 are different from those of the first embodiment, but the other parts are common to the first embodiment. For this reason, a different part from 1st Embodiment is mainly demonstrated, and illustration is abbreviate | omitted or abbreviate | omitted about the part which is common in 1st Embodiment. The combustion system 11 of the third embodiment has the same configuration as the overall configuration of the first embodiment shown in FIG.

The chamber 25 (connection portion) is configured to be detachable with respect to the supply pipe 23 of the existing boiler equipment or the like. The chamber 25 is continuous with the first end 42 connected to the upstream side of the supply pipe 23, the second end 43 connected to the downstream side of the supply pipe 23, and the first end 42, and the supply pipe A first portion 44 having an inner diameter greater than the inner diameter of the first portion 44, a second portion 45 that is continuous with the first portion 44 and the second end portion 43 and is tapered, and the first portion 44 and the second portion. 45 and a collision plate 61 that faces the second nozzle portion 32 and an inspection hole 46 provided in the second end portion 43.

The collision plate 61 includes a plate-like portion 62 and a protruding portion 63 that protrudes from the plate-like portion 62 toward the second nozzle portion 32. The protruding portion 63 has, for example, a conical shape with a tip portion facing the second nozzle portion 32 as a whole, and the conical tip portion is removed to form a rounded shape.

The second nozzle portion 32 is provided along the direction in which the supply pipe 23 extends. For this reason, the 2nd nozzle part 32 can inject high pressure water along what is called a fuel flow direction.

The water jetted at a high pressure from the second nozzle part 32 hits the collision plate 61 and is instantly crushed and diffused into the main liquid fuel while being atomized. Further, mixing / dispersing is further promoted by Karman vortices (schematically indicated by arrows in FIG. 7) generated behind (downstream) the collision plate 61. The collision plate 61 may be required to be installed when the amount of water injection from the nozzle is large and the nozzle diameter needs to be increased. However, if the nozzle injection amount is small and the diameter is small, the collision plate 61 You may atomize by pressure injection like 1st Embodiment, without using 61. FIG.

According to this configuration, the chamber 25 includes the first end 42 connected to the upstream side of the supply pipe 23, the second end 43 connected to the downstream side of the supply pipe 23, and the first end 42. It is continuous, has a larger inner diameter than the inner diameter of the supply pipe 23, is continuous with the first portion 44 provided with the second nozzle portion 32, the first portion 44 and the second end portion 43, and has a tapered shape. And a collision plate 61 provided at the boundary between the first portion 44 and the second portion 45 and facing the second nozzle portion 32.

According to this configuration, even in the structure in which the collision plate 61 is provided in the chamber 25, it is possible to generate water emulsion fuel in which water is atomized and diffused into the main liquid fuel. Furthermore, since Karman vortices can be generated behind the collision plate 61 (downstream side), the water particles and the main liquid fuel can be mixed efficiently, and the water particles can be dispersed in the main liquid fuel.

Referring to FIG. 8, a fourth embodiment of the combustion system will be described. The combustion system 11 of the fourth embodiment is different from the first embodiment in that it has the mixed liquid device 71 and a part of the configuration of the high-pressure pump device 14, but the other parts are the first. This is common with the embodiment. For this reason, a different part from 1st Embodiment is mainly demonstrated, and illustration is abbreviate | omitted or abbreviate | omitted about the part which is common in 1st Embodiment.

The combustion system 11 includes a combustion device 12 (main liquid fuel operation device) configured by a boiler, a water emulsion fuel device 13 that generates water emulsion fuel, and a high-pressure pump device 14 that supplies water to the water emulsion fuel device 13. And a liquid mixture device 71 (second supply unit, supply unit), a combustion device 12, a water emulsion fuel device 13, a high-pressure pump device 14, and a control device 15 that controls the liquid mixture device 71.

Further, the combustion system 11 includes a second pipe 70 (second connecting portion, connecting portion) and an injection nozzle 72 that is connected to the liquid mixture device 71 and injects second fuel into the second chamber 70. In the middle of this, it has in the upstream (fuel injection pump 17 side) rather than the chamber 25 (connection part).

The mixed liquid device 71 (second supply unit, supply unit) can supply the second fuel different from the fuel (main liquid fuel) into the supply pipe 23. The liquid mixture device 71 receives a second fuel from a storage / stirring tank 73 (a storage / mixing tank, a second fuel tank) in which a second fuel different from the main liquid fuel is stored. A third pump 74 for sending the second fuel to the second chamber 70, a second fuel supply line 75 connecting the third pump 74 and the second chamber 70, and a storage / stirring tank 73 from the second fuel supply line 75. A second return circuit 76 returning inward, a second flow rate adjusting valve 77 provided in the middle of the second return circuit 76, a third pressure gauge 78 provided in the middle of the second fuel supply line 75, and a second fuel supply. And a second fuel flow meter 81 provided in the middle of the line 75. A fourth electromagnetic valve 82 is interposed between the second chamber 70 and the mixed liquid device 71.

The third pump 74 pressurizes the second fuel passing through the second fuel supply line 75 to make the pressure higher than the fuel passing through the supply pipe 23 (main liquid fuel).

Further, between the water supply line 35 of the high-pressure pump device 14 and the second fuel supply line 75 of the mixed liquid device 71, a communication line 83 and a fifth electromagnetic valve 84 provided on the communication line 83 are provided. Yes. Examples of the second fuel include various alcohols typified by ethanol and methanol, glycerin, BDF (registered trademark), crude vegetable oil, waste edible oil, waste oil, and the like. Ethanol includes ethanol obtained from cereals, sugar cane and vegetation. BDF (registered trademark) and crude vegetable oil are obtained from waste edible oil, palm, rapeseed, jatropha, algae and the like.

Subsequently, the combustion flow of this embodiment will be described. The combustion flow described below differs depending on the type of mixed fuel (second fuel) mixed with the main liquid fuel.

(When using alcohol as a mixed fuel)
First, the case where the mixed fuel is an alcohol such as ethanol or methanol will be described. An alcohol mixed with an arbitrary amount of water in advance is put into the storage / stirring tank 73, and an arbitrary amount is injected into the second chamber 70 while stirring is continued in the storage / stirring tank 73. In the case of this example, the injection nozzle 72 is the same as the second nozzle portion 32 of the first embodiment. Accordingly, the pressure of the aqueous alcohol solution from the injection nozzle 72 to the fuel flowing through the supply pipe 23 is appropriately set within a range of 0.5 MPa to 10 MPa higher than the pressure of the fuel pressurized by the fuel injection pump 17. ) Injecting, water in the aqueous alcohol solution is atomized by the discharge speed (or momentum) of the high pressure injection and the reaction force of the main liquid fuel, and at the same time, the water particles are mixed so as to be evenly dispersed in the fuel.

In this case, if the amount mixed with water is extremely small, the micro-explosive effect of water may not be sufficiently obtained, and the predetermined effect as a water emulsion fuel may not be obtained. For this reason, the optimum moisture content is found based on the combustion data. Note that when the mixed fuel is alcohol as in this example, water is mixed with alcohol in advance, so that the high-pressure pump device 14 for supplying water as in the first embodiment is not required.

(When glycerin is used as a mixed fuel)
Next, the case where the mixed fuel is glycerin will be described. The glycerin may contain KOH and NaOH washing residue used in the alkaline catalyst method in the purification process of BDF (registered trademark), and free fatty acids in BDF (registered trademark) purification of waste cooking oil. There is a need for removal of these residual materials or heat treatment.

* Glycerin is put into the storage / stirring tank 73 under these conditions, and fluidity is secured while heating / stirring. Although not shown, the heating unit is provided in each part of the storage / stirring tank 73 and the second fuel supply line 75. An arbitrary amount of glycerin is injected into the fuel (main liquid fuel) in the second chamber 70.

In the case of this example, as with the first embodiment, water (fuel that has been pressurized by the fuel injection pump 17) from the second nozzle portion 32 with respect to the fuel flowing through the supply pipe 23 and the second fuel (glycerin). The water pressure is appropriately set within a range of 0.5 MPa to 10 MPa higher than the pressure of the pressure.), And water is atomized by the discharge speed (or momentum) of the high pressure injection and the reaction force of the fuel and the second fuel. At the same time, the water particles are mixed so that they are evenly dispersed in the fuel.

In addition, if the glycerin mixed solution remains in the chamber 25, the supply pipe 23, or the circulation line 27, it may cause trouble. For this reason, injection | pouring of glycerol is stopped several minutes before the stop of a main liquid fuel operation apparatus, and glycerol does not remain. Further, in order to prevent the injection nozzle 72 from being clogged, the injection nozzle 72 is cleaned with water. When cleaning the injection nozzle 72, the fourth electromagnetic valve 82 is closed and the fifth electromagnetic valve 84 is opened to pass water from the high-pressure pump device 14 to the communication line 83. The inside of the chamber 70 is washed with high-pressure water. Since glycerin has a higher viscosity and less heat than other mixed fuels, a balance between the dilution ratio of water and the combustion effect is required.

(When using crude vegetable oil, BDF (registered trademark), waste edible oil, waste oil as mixed fuel)
Furthermore, when the mixed fuel is a crude vegetable oil, BDF (registered trademark) (Bio Diesel Fuel), waste edible oil, or waste oil, it cannot be added to these, and heating is required. First, these fuels from which dust and the like have been removed are put into the storage / stirring tank 73. Heated by a heating unit (not shown) and sent from the third pump 74 to the second chamber 70 with stirring. These fuels do not greatly affect the main liquid fuel if the viscosity is adjusted by heating. However, the higher the mixability, the more the air management and fuel discharge conditions are constant. Therefore, the injection nozzle 72 has a larger diameter than the second nozzle part 32, and has a lower pressure than the water injected from the second nozzle part 32 and a higher pressure than the main liquid fuel, and may be dispersed. The particle diameter of the particles ejected from the ejection nozzle 72 need not be too particular. In order to prevent the injection nozzle 72 from being clogged, the same treatment as that for glycerin is performed after the injection is stopped.

After the injection of BDF (registered trademark), water is supplied from the second nozzle portion 32 to the high pressure (fuel) with respect to the fuel flowing through the supply pipe 23 and the second fuel (BDF (registered trademark)), as in the first embodiment. The water pressure is set appropriately within the range of 0.5 MPa to 10 MPa higher than the pressure of the fuel pressurized by the injection pump 17.) The discharge speed (or momentum) of the high pressure injection and the fuel and the second fuel While the water is atomized by the reaction force, at the same time, the water particles are mixed so that the water particles are evenly dispersed in the fuel to produce a water emulsion fuel.

According to the fourth embodiment, the combustion system 11 is provided in the supply pipe 23 via the second connection part provided in the supply pipe 23 and upstream of the connection part in the vicinity of the connection part and the second connection part. And a second supply unit for supplying a second fuel different from the fuel, and the supply unit is also connected to the second connection portion.

According to this configuration, a different type of second fuel can be mixed with the fuel (main liquid fuel). Furthermore, since the supply unit which can supply water is connected also to a 2nd connection part, the 2nd connection part can be wash | cleaned using the water of a supply unit. Thereby, even when a highly viscous fuel is used as the second fuel, the clogging of the second connection portion can be prevented, and the long-term stable operation and smooth operation of the combustion system 11 can be enabled.

According to the fourth embodiment, the combustion system 11 includes a fuel tank 16, a pump that pressurizes fuel supplied from the fuel tank, a first nozzle unit that injects pressurized fuel into the combustion chamber, A supply pipe 23 that connects the first nozzle part and the pump and through which the pressurized fuel passes, a connection part provided in the middle of the supply pipe 23 in the vicinity of the first nozzle part, and a supply through the connection part A supply unit that supplies an aqueous alcohol solution into the pipe 23, and a second nozzle portion 32 that is interposed between the supply unit and the connection portion and that can atomize the aqueous alcohol solution into the connection portion and spray it.

According to this configuration, when a fuel (alcohol) different from the main liquid fuel is mixed and used as a fuel, the mixing of the two types of fuel and the emulsification of the mixed fuel are collectively performed. It can be carried out. Thereby, it is not necessary to add only water separately, and the structure of the combustion system can be simplified. Thereby, the initial cost can be reduced when the emulsion apparatus is introduced into the existing equipment.

In recent years, biofuel (vegetable oil) has attracted attention, but the amount of biofuel produced is absolutely insufficient relative to main liquid fuel (petroleum, etc.). For this reason, in order to reduce the environmental load, for the next several decades, mixed combustion, in which main liquid fuel and biofuel are mixed and burned, is attracting attention. Ethanol is one of biofuels. Biofuels include ethanol, glycerin, BDF (registered trademark), crude vegetable oils (low-processed products made of palm, jatroha, etc.), waste edible oils, and the like.

However, the main liquid fuel (light oil, A heavy oil, C heavy oil) and vegetable ethanol oil are not soluble at all and cannot be simply mixed and burned. Similarly, glycerin is not soluble in main liquid fuel (light oil, A heavy oil, C heavy oil). According to the above-described configuration, it is possible to achieve both of the advantages that the combustion efficiency can be further improved by water emulsification while realizing mixed combustion in which fuel (main liquid fuel) and alcohol (or glycerin) are mixed. In addition, when the situation changes in the future and the vegetable oil supply system is in place, it is easy to change the mixing ratio, such as changing the ratio of the second fuel (vegetable oil) to the fuel (main liquid fuel). It is.

A fifth embodiment of the combustion system will be described with reference to FIG. Although the combustion system 11 of 5th Embodiment differs from the thing of 1st Embodiment by the point whose application object is a ship, the other part is common in 1st Embodiment. For this reason, a different part is mainly demonstrated and illustration is abbreviate | omitted or abbreviate | omitted about the part which is common in 1st Embodiment.

The combustion system 11 includes a fuel tank 16 in which fuel (main liquid fuel, for example, petroleum) is stored, a booster pump 91 that receives fuel supply from the fuel tank 16, and a fuel that connects the fuel tank 16 and the booster pump 91. A pipe 18, a first flow meter 21 provided in the fuel pipe 18, a first pressure gauge 24 provided in the middle of the fuel pipe 18, a flow rate adjusting valve 92 that adjusts the flow rate of fuel sent from the booster pump 91, A fuel injection pump 93 for injecting fuel pressurized by the booster pump 91 into the ship engine 94, a supply pipe 23 for connecting the booster pump 91 and the fuel injection pump 93, and a ship engine 94 having a combustion chamber ( Engine), a fuel return line 95 for returning excess fuel from the fuel injection pump 93, and a fuel return line 95 Water is supplied into the supply pipe 23 via the third flow meter 96 and the chamber 25 (connection part) provided in the middle of the supply pipe 23 in the vicinity of the fuel injection pump 93 and the chamber 25 (connection part). And a nozzle unit 97 interposed between the high-pressure pump device 14 and the chamber 25.

The configuration of the nozzle portion 97 is substantially the same as the configuration of the second nozzle portion 32 of the first embodiment. For example, a standard straight nozzle (orifice diameter: CP small hole diameter nozzle 0.3 mm) is employed.

In this embodiment, the fuel return line 95 is connected to the suction side (upstream side) of the booster pump 91 instead of being connected to the service tank as in a fuel supply system in a conventional ship. As a result, the water in the water emulsion fuel is prevented from being steamed and accumulated in the service tank in the service tank. Further, the fuel stored in the fuel tank 16 for ship engines is often, for example, heavy oil (for example, C heavy oil).

The pressure of the fuel pressurized by the booster pump 91 and passing through the supply pipe 23 is, for example, 0.5 MPa, but may be a pressure in the range of 0.5 MPa to 5 MPa. In the fuel injection pump 93, the fuel pressure is increased to, for example, about 200 MPa. The pressure of the general fuel injection pump 93 is in the range of 5 MPa to 200 MPa, and the pressure of the fuel pressurized by the fuel injection pump 93 of the present embodiment may be set appropriately within these ranges. it can. Between the booster pump 91 and the fuel injection pump 93, that is, the supply pipe 23 is heated in the range of 80 ° C. to 150 ° C. However, the pressure applied by the booster pump 91 prevents the water particles in the water emulsion fuel from being vaporized.

The high-pressure pump device 14 includes a water tank 33 in which water is stored, a high-pressure pump 34 (pump) that receives supply of water from the water tank 33 and sends pressurized water to the nozzle unit 97, A water supply line 35 connecting the second nozzle portion 32, a return circuit 36 returning from the water supply line 35 into the water tank 33, a flow rate adjusting valve 37 provided in the middle of the return circuit 36, and a water supply line 35 A second pressure gauge (not shown) provided in the middle and a second flow meter 38 provided in the middle of the water supply line 35 are provided. The pressure of the water pressurized by the high-pressure pump 34 is, for example, 1.5 MPa, but may be appropriately set within a range 0.5 MPa to 10 MPa higher than the pressure of the fuel pressurized by the booster pump 91. it can. A third electromagnetic valve 41 is interposed between the chamber 25 and the high-pressure pump device 14.

In this embodiment, the fuel in the fuel tank 16 is sent to the booster pump 91. The fuel pressurized by the booster pump 91 undergoes flow rate adjustment by the flow rate adjustment valve 92 and is supplied to the fuel injection pump 93 via the supply pipe 23. In the chamber 25, pressurized water is jetted from the nozzle portion 97. The discharge speed (or momentum) of the high-pressure jetted water and the reaction force of the main liquid fuel make the water fine and at the same time mix the water and fuel so that the water particles are evenly dispersed in the fuel. The The water emulsion fuel generated in this way is sent to the fuel injection pump 93, and is injected into the combustion chamber of the marine engine 94 from an injection nozzle (not shown) and burned. In the ship engine 94, since water emulsion fuel is used, discharge of Nox, soot and the like is reduced. Water emulsion fuel that has not been used in the fuel injection pump 93 is returned to the suction side (upstream side) of the booster pump 91 via the fuel return line 95. In order to make the water content of the water emulsion fuel constant, in the combustion system 11 of the present embodiment, when the ratio of the water emulsion fuel returned from the fuel return line 95 is higher than the main liquid fuel, The amount of water supplied by the nozzle part 97 (chamber 25) is reduced to keep the water content constant.

According to the fifth embodiment, the combustion system 11 injects the fuel tank 16, the booster pump 91 that pressurizes the fuel supplied from the fuel tank 16, and the fuel pressurized by the booster pump 91 into the engine. The fuel injection pump 93, the booster pump 91 and the fuel injection pump 93, and the supply pipe 23 through which the pressurized fuel passes, and the connection portion provided in the middle of the supply pipe 23 in the vicinity of the fuel injection pump 93 And a supply unit that supplies water into the supply pipe 23 via the connection part, and a nozzle part 97 that is interposed between the supply unit and the connection part and that can atomize and inject water into the connection part.

According to this configuration, high-pressure water is mixed with the pressurized fuel to produce a water-emulsion fuel, and thereafter, the water-emulsion fuel can be maintained in a high-pressure state until it is used by the fuel injection pump 93. Thereby, in the microparticulated water particles, the internal pressure due to the surface tension is increased, particle collapse and particle bonding are prevented, and aggregation of water in the water emulsion fuel can be prevented. Usually, the fuel pressure between the booster pump 91 and the fuel injection pump 93 is generally in the range of 0.5 MPa to 1.0 MPa. In general, the supply pipe 23 and the fuel in the meantime are heated, and the heating temperature is approximately 80 ° C. to 150 ° C. although it varies depending on the fuel viscosity. However, in the above pressure range, there is no problem that the water particles in the water emulsion fuel are vaporized.

Further, according to the present embodiment, since water emulsion fuel can be generated immediately before being used in the fuel injection pump 93, there is no time for water to aggregate in the water emulsion fuel as described above. For this reason, it can prevent that the said malfunction arises in water emulsion fuel. Furthermore, according to the present embodiment, the mixer and the water emulsion fuel dedicated pump that are conventionally required are not required, and the apparatus configuration can be simplified and the cost can be reduced. In addition, no major modifications are required to the existing facilities of the ship. Further, since the water emulsion fuel can be generated without using an expensive surfactant, the running cost of the apparatus can be reduced.

Note that the provision of the connection portion in the vicinity of the fuel injection pump 93 means that the connection portion is in the vicinity of the fuel injection pump 93, and the supply pipe 23 is the end of the supply pipe 23 on the fuel injection pump 93 side. The connection portion is provided within a range of approximately one third of the total length of the pipe (more preferably, 10% to 20% of the total length of the supply pipe 23).

Furthermore, NOx reduction requests for ships have been accelerating year by year, and the IMO (World Maritime Organization) will comply with secondary regulations (IMO-MARPOL Convention) for engines with an output of 130 kW or more built after 2011. In addition, each engine maker is working harder toward the third regulation in 2016.

However, the technical difficulty to meet the tertiary regulations is extremely high, and what is currently promising is SCR (denitration system) technology and EGR equipment. According to this embodiment, in the SCR device, the cost of maintenance can be reduced by reducing the amount of maintenance due to the reduction in soot, or by reducing the amount of expensive reducing agent (ammonia) used by reducing NOx. Also in the EGR device, in a recent announcement, there is a report that the amount of NOx can be reduced to a level close to the 2016 regulation value by using it together with emulsion fuel.

The structure of the device that injects only water makes it extremely small, and can be installed with an installation space of about 0.5 m ² and is not related to the height difference or distance from the ship engine 94. Or, there is an advantage that it can be retrofitted even on the deck of a ship other than the engine room.

In addition, in the first to fifth embodiments, it goes without saying that the present invention can be variously modified without departing from the spirit of the invention. In addition, a new invention can be configured by combining configurations of different embodiments.

DESCRIPTION OF SYMBOLS 11 ... Combustion system, 14 ... High pressure pump apparatus, 16 ... Fuel tank, 17 ... Fuel injection pump, 22 ... Combustion nozzle, 23 ... Supply pipe, 25 ... Chamber, 32 ... 2nd nozzle part, 32A ... 2nd nozzle, 42 ... 1st end part, 43 ... 2nd end part, 44 ... 1st part, 45 ... 2nd part, 51 ... Restriction part, 61 ... Colliding plate, 70 ... 2nd chamber, 71 ... Mixed liquid apparatus, 72 ... Injection Nozzle, 91 ... Booster pump, 93 ... Fuel injection pump, 97 ... Nozzle part

Claims

A fuel tank,
A pump for pressurizing the fuel supplied from the fuel tank;
A first nozzle for injecting the pressurized fuel into the combustion chamber;
A supply pipe connecting the first nozzle part and the pump and through which the pressurized fuel passes;
A connection portion provided in the middle of the supply pipe in the vicinity of the first nozzle portion;
A supply unit for supplying water into the supply pipe via the connection part;
A second nozzle part interposed between the supply unit and the connection part and capable of atomizing and spraying water into the connection part;
A combustion system.
The combustion system according to claim 1, wherein the pressure of the water is 0.5 MPa to 10 MPa higher than the pressure of the pressurized fuel.
The combustion system according to claim 2, wherein the connecting portion is a chamber that is detachable from the supply pipe.
The combustion system according to claim 3, wherein the second nozzle portion is installed in any one of a direction orthogonal to a direction in which the supply pipe extends and a direction oblique to the direction in which the supply pipe extends.
The second nozzle portion includes a plurality of second nozzles,
The combustion system according to claim 4, wherein the plurality of second nozzles are alternately arranged along a direction in which the supply pipe extends.
The connecting portion is
A first portion provided with the second nozzle portion;
A throttle portion provided on the downstream side of the second nozzle portion of the first portion and having an inner diameter smaller than other portions in the first portion;
The combustion system according to claim 5.
A second connecting portion provided in the supply pipe on the upstream side of the connecting portion in the vicinity of the connecting portion;
A second supply unit for supplying a second fuel different from the fuel into the supply pipe through the second connection portion;
With
The combustion system according to claim 3, wherein the supply unit is also connected to the second connection portion.
The chamber is
A first end connected to the upstream side of the supply pipe;
A second end connected to the downstream side of the supply pipe;
A first portion that is continuous with the first end portion and has an inner diameter larger than an inner diameter of the supply pipe and is provided with the second nozzle portion;
A second portion that is continuous with the first portion and the second end portion and has a tapered shape;
A collision plate provided at a boundary between the first portion and the second portion and facing the second nozzle portion;
A combustion system according to claim 3.
A fuel tank,
A pump for pressurizing the fuel supplied from the fuel tank;
A first nozzle for injecting the pressurized fuel into the combustion chamber;
A supply pipe connecting the first nozzle part and the pump and through which the pressurized fuel passes;
A connection portion provided in the middle of the supply pipe in the vicinity of the first nozzle portion;
A supply unit for supplying an aqueous alcohol solution into the supply pipe via the connection part;
An injection nozzle that is interposed between the supply unit and the connection portion, and can atomize and inject the aqueous alcohol solution into the connection portion;
A combustion system.
A fuel tank,
A booster pump that pressurizes the fuel supplied from the fuel tank;
A fuel injection pump for injecting the fuel pressurized by the booster pump into the engine;
A supply pipe connecting the booster pump and the fuel injection pump and through which the pressurized fuel passes;
A connecting portion provided in the middle of the supply pipe in the vicinity of the fuel injection pump;
A supply unit for supplying water into the supply pipe via the connection part;
A nozzle part interposed between the supply unit and the connection part, and capable of atomizing water into the connection part and spraying it;
A combustion system.